Fungal fruiting bodies are a good indicator of internal wood decay and potentialstructural deficiencies that create unseen hazardous conditions.

Developing aTree Care Program.

Treesplay an important role on golf c(Jurses,and theircare and management should be planned carefully.

by JAMES SKORULSKI

TIESare very important parts ofmost golf courses. Many golferswill protect trees with a zeal

matched only by their love for the gameitself. This blind affection for trees canresult in poor judgement or misguidedpriorities in tree planting and mainte-nance programs. Proper planning andmaintenance often become secondary

as the emphasis is placed on plantingmore and more trees. This philosophyoften leads to hasty decisions withnew plantings, resulting in poorlypositioned trees that consist of speciesthat may not be well suited for the golfcourse or the particular planting site.This can create immediate mainte-nance headaches with the trees and will

likely lead to future agronomic prob-lems with the turf. The lack of a goodpreventative maintenance programalso is apparent at such golf courses,as many of the existing trees havestructural problems or poor growthform and appearance.

Golf courses with good reputationsfor their tree plantings realized long ago

MARCH/APRIL 1996 1

the value of a comprehensive programto care for existing trees and properlyplan for new tree plantings when andwhere they become necessary. Thoseefforts have paid off handsomely withbalanced age classes of healthy, well-formed tree species and a minimum oftree-related agronomic problems. Thisarticle will examine strategies that canbe used to develop the foundation fora good tree maintenance program, andexamine specific pruning practices thatcan be used to maintain healthier,more attractive trees and help rectifyagronomic problems.

Program OrganizationThere are several ways to develop a

tree care program. Golf courses thatchoose to complete the majority ofwork with their own staff will employa full-time arborist or tree specialistwho has both the knowledge andexperience to help develop and com-plete the practices. The extent of thework completed will vary dependingon experience, available equipment,and the amount of liability the golfcourse is willing to assume. In manyinstances the arborist/tree specialistwill complete smaller scale pruning,tree removal, and pest managementwork, and have the larger sprayoperations, climbinglbucket work, andmajor tree removals completed byoutside contractors.

A large number of colleges and uni-versities offer degree programs in forestand shade tree management andarboriculture. Graduates from suchprograms would be well suited forthe position. Students might also beavailable for summer placement jobson the golf course and eventually workinto a full-time position as they gainexperience. The position requires over-all knowledge of trees and their specificrequirements, including pruning, fer-tility, irrigation, and pest managementneeds. Tree pruning and removal skillsare a must, as is the ability to properlyidentify and evaluate hazardous trees.

This is not to say that a good treemaintenance program cannot be de-veloped without first hiring an experi-enced arborist. The golf course super-intendent may have the necessarybackground to develop and oversee arelatively good program if he is fortu-nate enough to possess the skills men-tioned above and have the necessarytime~ An even larger amount of thework would probably be completed byoutside contractors with a programorganized in this way.

Tree InventoryA tree inventory is beneficial for any

level of tree maintenance completed onthe golf course. You have to know thetree species, its specific requirements,and the life expectancy in order to planand prioritize pruning work and other

maintenance and planting programs.This information is critical even if theprimary maintenance work is com-pleted by outside contractors. The in-ventory should identify tree species,map their locations, estimate approxi-mate age class and tree condition,provide site characteristics, and anyother pertinent notes. The tree's esti-mated intrinsic and monetary valuesmight also be included in the inventory.Computer software, such as the TrimsTree Management Program, can behelpful in producing the inventory.

Identifying the various tree speciesmay be the most intimidating hurdle incompleting the inventory. The servicesof an arborist or employee with train-ing in tree identification are definitelyrecommended, especially if a superin-tendent's dendrology skills have faded.The inventory might serve as a goodproject for a summer placement stu-dent with knowledge in tree identifi-cation. There are also many goodbooks and keys available to aid inthe identification process. Universityspecialists, extension agents, or localnursery personnel can also provideassistance if the challenge is too great.Estimating monetary values is morecomplex and should be left to anexperienced arborist.

Tree EvaluationThe tree plantings should be thor-

oughly inspected on an annual basis to

Applying Round-up to control grasses at the base of trees can be a trickyprocess. By using a form and a wick applicator, a very clean line is produced.

evaluate their condition and establishmaintenance priorities. The inspectionwould determine where tree pruningwork, individual tree removals, standthinning, and new tree plantings maybe required. Fertility, pest management,and. other maintenance programsshould be developed based on theresults of the evaluation. Informationfrom the evaluation and tree inventory,together with input from the superin-tendent, golf professional, and greencommittee members should be used totarget sites where trees affect turfquality or negatively influence play.

Pruning TechniquesPruning work is a primary part of tree

maintenance programs. Unfortunately,the work is not fully utilized in manygolf course tree care programs. Pruningis used to enhance or modify a tree'snatural growth form. Remedial pruningis completed regularly to remove dis-eased, damaged, poorly attached, orcrowded branches to improve a tree'sstructure and appearance. Tree size canbe maintained to a certain extent withpruning. Pruning is also used to helptrain young trees. Pruning can stimulateflowering in ornamental trees and vigorin stressed or stagnated trees. Selectivepruning is frequently completed on golfcourses to increase light penetrationand air flow to the tree and surroundingareas. Tree canopies are also raisedfrom the ground to gain more air move-

ment and access below the tree. Finally,root pruning is used to remove girdlingroots from the base of tree trunks andwhere tree roots are aggressively com-peting with the turf.

The impact of the pruning work onthe tree can be minimized by properlypositioning and completing the cut.The old standard flush cut is no longerrecommended except for adventitiouswater sprouts or sucker branches.Branches should instead be cut alongthe outside edge of branch bark ridge(shoulder rings) and collar to minimizethe wound's size and allow the treeto callus over the cut more quickly.There are several techniques followedto make a proper cut, depending onbranch size. Smaller branches are oftencut with hand shears or hand saws,while large hand saws or chain saws areused for larger cuts. Larger branchesrequire a series of cuts to prevent thebark and wood from tearing and split-ting back into the tree. The first cut ismade on the lower side of the branch,usually 1 to 2 feet from the crotch. Thecut is made upward about a quarter ofthe diameter or until the saw begins tobind. The second cut is completed ontop of the branch and placed outsidethe first cut by 1 or 2 inches. Thesecond cut allows the branch to breakcleanly off the tree. The final cut is thenmade at the crotch, as recommendedabove. Heavier branch stubs may needto be undercut and/or supported

during the final cut to avoid tearingthe bark.

Applying wound dressing is nolonger recommended. The dressingsmay actually delay the process bywhich the tree recovers from thewound. Paints are sometimes used tomask or improve a wound's appear-ance, but those too will have no otherbeneficial effects. Trees naturally isolatethe wounds by developing a chemicalbarrier in a process termed compart-mentalization. The barrier preventsmost decay fungi and bacteria fromentering surrounding wood as the treeproduces callus tissue which in timewill cover over the wound.

The timing of the pruning operationsdepends on the purpose of the pruningwork, the type of tree, and its condition.Minor or light pruning work can becompleted at any time of the year.Dead, diseased, weak, or heavilyshaded branches can also be removedat any time with little negative effecton the tree. Plant development will beaffected least if the pruning work iscompleted prior to the period of mostrapid growth. The majority of deciduoustrees can therefore be pruned duringwinter dormancy and until springgrowth resumes to correct structuralproblems. Evergreen trees should bepruned just prior to spring growth tominimize the chance of cold tempera-ture injury around the wounds. Treessuch as maples, birch, and elm can

After several years, moss has started toestablish, creating a nice groundcover.

Controlling grasses around the base of trees can speed upmowing and prevent mower damage, but it also creates adelicate situation when it comes to control measures. Carefulapplications need to be made to avoid injury to the tree.

If left untouched, this girdling root could eventually kill the tree.

Before the girdling becomes too advanced, removal of the offending root can extend the life of the tree.

4 USGA GREEN SECfION RECORD

Site inspections should include reviewing potential agronomic problems caused by trees. The trees surrounding this green need tobe selectively pruned to permit more light to penetrate to the green.

bleed heavily if pruned in early spring.The bleeding can be minimized if prun-ing is completed in very late fall, earlywinter, or mid-spring. Heavy bleedingcan create unsightly stains and delaythe onset of callus tissue formation.

Reducing the tree's growth rate andsize is accomplished most effectively ifpruning work is completed after theseason's growth flush has occurred.Pruning work should be scheduled inspring to midsummer for this purpose.Keep this in mind when thinning treecanopies to gain additional light andair flow. Late summer and fall prun-ing work is least favorable, as largerwounds recover more slowly and aremore susceptible to the decay fungithat sporulate in fall. Callusing is mostrapid if pruning work is completedprior to or soon after tree growthresumes in spring. Use even more carewhen completing pruning cuts dur-ing and immediately following the

rapid spring growth period, as thebark is particularly tender and is easilytom.

Pruning Young 'freesNursery stock should have relatively

good growth form. Do not acceptplanting material if the structuralbranches are not uniformly spaced,are too close together, or are poorlyattached. However, even good qualitynursery stock will likely require somepruning work as the trees mature tomaintain good structure and branch-ing. Pruning should be minimal at thetime the tree is planted. Broken ordamaged branches can be removed, ascan adventitious shoots. It is best tocomplete major pruning work duringthe tree's early establishment period, aspruning wounds are smaller and thework easier to complete. Large-scalecorrective pruning should be spread

over several years to avoid excessivestress on younger trees.

'fraining very young trees is a com-plex matter requiring knowledge of thetree's growth form and function on thegolf course. Young trees should beinspected for uniformly spaced verticaland radial branching and sound branchattachments along the main leader.Remember, these young branches serveas the main scaffold branches as thetree matures. Larger growing treesshould have wider spaced main orscaffold branching along the trunkfor optimum strength, while smallergrowing trees should have more closelyspaced branching. The lateral branchesshould not be larger than the trunk ormain leader, as they compete for domi-nance and result in a weak attachment.Horizontal branching and wider anglebranch attachments usually result instronger connections, which are moredesirable.

MARCH/APRIL 1996 5

Root pruning is a common practice on golf courses where tree root competition reduces turf quality. Recent studies have found thatroot pruning work can be completed at distances closer to the tree than once thought, if the remaining tree root system is left intact.

Proning Mature Trees

Corrective pruning measures. re-quired for mature plantings generallyare more severe and costly to complete,especially if the trees received littlecare in the past. Inspect the tree canopyand specifically look at scaffold ormain branching to make sure the tree'scanopy is well formed and in balance.Poor quality branches, or those that arediseased, dead, or interfering with eachother should be removed. This processis often referred to as dead wooding.Tree canopies that create excessiveshade, block air movement, affect play,or crowd each other can be addressedthrough crown reduction or crownthinning. Raising the crown is theterm used for pruning work completedto raise the tree canopy off the groundto increase light penetration and airmovement.

6 USGA GREEN SECTION RECORD

Dead wooding is especially impor-tant for older trees that contain haz-ardous branching or decayed wood.Such wood should be removed, alongwith any vines or foreign material. Thistype of pruning is often completedprior to initiating crown thinning orreduction work. Removing the weakerbranches and dead wood makes iteasier to determine the additionalpruning work required. Dead woodingalso is an excellent tool used to managecertain pests. However, diseases suchas fire blight and other canker-formingdisorders can be spread through prun-ing wounds, making it necessary todisinfect pruning tools following eachcut.

Crown thinning is completed tohighlight a tree's branching and toincrease light penetration and airmovement through the canopy. Treeswith overly dense canopies benefit

from opening the canopy. The addi-tionallight promotes stronger growthof the remaining branches, encourageslateral branch development, and in-creases branch tapering to make thetree less susceptible to storm damage.Wind resistance can also be reducedby selective thinning work. Crownthinning can result in the removal ofa third or more of the tree's canopy,which should not affect vigorousdeciduous trees. However, beech, birch,hornbeam, eucalyptus, walnut, andmost conifer trees are less tolerant ofsevere pruning and therefore shouldhave less of the canopy removed at anyone time.

Crown reduction is also a relativelycommon procedure used to keep treeswithin size requirements. This type ofpruning is often used to overcomeearlier mistakes in planting judgement.Tree size can be controlled most effec-

Sinclair, W. A., Lyon,H. H., and Johnson,W. T. 1987. Diseasesof Irees and Shrubs.Ithaca/London, Cor-nell Unversity Press.

Tuffs, L. October,1994. Iruce in theTrenches. "Hort.Week."

JAMES SKORULSKIis an agronomist inthe NortheasternRegion of the USGAGreen Section.

following the operation. Pruning morethan one side of a tree in a given yearwill cause more stress and could leavethe tree less stable.

Trees will continue to be a veryimportant part of most golf courses.Hopefully, this article has changed theway you look at trees and tree careprograms at your golf course. It isimportant to remember that the pas-sion reserved for trees does not haveto be devoted entirely to new plantingprograms. Institute a new philosophyfor trees that addresses maintenanceneeds equally with new planting pro-grams. Develop a tree inventory and, ifpossible, add a tree specialist to yourstaff, or become more familiar withtrees yourself to better develop andimplement pruning and other mainte-nance programs. The existing trees willdefinitely benefit, as will new plantings,which will be made with more scrutiny.Turf and trees can coexist nicely, espe-cially if we do not allow blind affectionto get in the way of reality.

Literature CitedHarris, R. W. 1983. Arboriculture Care ofIrees, Shrubs, and Vines in the Land-scape. Englewood Cliffs: Prentice Hall,Inc.

Harris, R. W. Arboriculture: IntegratedManagement of Landscape Irees, Shrubs,and Vines. 2nd ed., Regents/Prentice Hall,

Englewood Cliffs,LCC#91-19477.

Miller, Jr., F. D., andNeely, D. 1993. TheEffects of Irenchingon Growth and PlantHealth of SelectedSpecies of ShadeIrees. "J. Arboricul-ture" 19(4):226-229.

season when the branches are in fullleaf. This operation is often objection-able to many people, who dislike theunnatural appearance it can create. Itis possible to raise the canopy heightand still maintain a somewhat naturalappearance if the work is donecarefully and extended over severalseasons.

Root pruning is another commonpractice on golf courses where treeroot competition reduces turf quality.Individual tree roots may also have tobe pruned manually if they begin togirdle the tree. Tree roots are severed ata 12- to 20-inch depth using a powertrencher, vibratory plow, backhoe, orroot cutting saw. Standard recommen-dations are to provide 1 foot of distance

.between the pruning trench and treeper inch of tree diameter at chestheight. Recent studies indicate, how-ever, that pruning along one side ofmoderately sized, healthy trees can becompleted at. distances of 3 feet andcloser without seriously affecting thetree's growth rate or survival as longas the remaining root system is intactand unrestricted. Larger and slowergrowing trees might show more severeeffects from such close pruning. Thestudy also demonstrated that thenegative effects of severe single- andmultiple-side root pruning could bereduced by thinning the tree's crown

This 12-inch drainage pipe was filled withwillow roots three months after installation.

tively if pruning is initiated before thetree reaches the desired size. Pruningcuts will be smaller and the tree's ap-pearance less affected. Trees that re-quire frequent crown reduction workprobably should be replaced, as theirnatural appearance will be altered.Crown reduction also can be an effec-tive means to address overcrowded treestands. The canopies of the smaller andless desirable trees should be severelypruned, allowing the surrounding treesto develop properly. The pruned treeseventually will be removed as the pre-ferred trees develop.

Thinning-out, heading, and pol-larding are pruning techniques used incrown reduction. Thinning-out is thepreferred technique when the tree'snatural growth form is to be main-tained. It involves pruning branchesback to lower laterals (drop-crotching)that are at least a third the diameter ofthe branch being removed. Heading isused to drastically reduce canopy size.It involves pruning the main branchesback to stubs. This form of pruning canleave very large wounds that may nevercallus, thus providing sites for decay. Italso results in very dense, upright, andvigorous branching immediately belowthe cut. The resulting branching is un-natural in appearance, poorly attached,and generally not safe. It is not a recom-mended technique for most situations.Pollarding is a type .of heading opera-tion used in moreformal landscapesituations to keeplarger growing treesunder size control.This technique israrely used on golfcourses.

Raisingthe crownis often completedon conifer treeswhose lower branchwhorls affect main-tenance or play, orblock sun and airflow. This is com-pleted by removinglower branchescompletely or prun-ing them back tothe next largest, up-right lateral branchto reduce weight.Similar work iscompleted on de-ciduous trees dur-ing the growing

MARCH/APRIL 1996 7